diff --git a/phantom/index.d.ts b/phantom/index.d.ts
index da6d270467..bd337dc624 100644
--- a/phantom/index.d.ts
+++ b/phantom/index.d.ts
@@ -47,7 +47,7 @@ export interface ICookie {
     path: string,
     httponly?: boolean,
     secure?: boolean,
-    expires?: Date
+    expires?: string
 }
 
 export interface IPaperSizeOptions {